1. Field of the Invention
Systems and methods consistent with the present invention relate to configuring a device in a network, and more specifically, to configuring a device by registering information of the device to a server without having to directly input the information of the device.
2. Description of the Related Art
Diverse information may be exchanged over networks. If a sender wants to transfer a sensitive message via an electronic mail or an electronic document delivery system, a mechanism is required for the sender to ensure that an intended recipient receives the message, and for the recipient to ensure that the creator of the message is the authentic sender.
Encryption and decryption technology encrypts information to be transmitted using a key value of the information. The recipient decrypts the received information using the key value in order to recover the original information. Thus, the use of encryption and decryption prevent a third party from obtaining the original information from the sender even if the third party intercepts the transmission.
An encryption and decryption system may include a symmetric key cryptography and an asymmetric key cryptography. In symmetric key cryptography, a key Ke for the encryption is the same as a key Kd for the decryption. This may be expressed as Ke=Kd.
Symmetric key cryptography features rapid encryption and decryption, but has disadvantages in key management and key exchange. For instance, each set of a sender and a recipient needs to have a different key from other sets of senders and recipients. Thus, the number of keys to be managed increases. In addition, since both the sender and the recipient need to have the same key, the key is subject to the exposure to others during the key exchange, which complicates the key distribution.
The rapid development of a network environment demands efficient key management and key distribution for secure communications between a plurality of anonymous users. An efficient cryptography is required to enable secure communications among multiple users using the relatively small number of keys and to apply to digital signatures. In response to this need, public key cryptography has been introduced.
Public key cryptography uses a public key and a private key for the authentication, the signatures, and the encryption. As the encryption key is different from the decryption key, the public key cryptography is known as an asymmetric cipher. The public key is exposed to others but the private key, which is called a secret key, is kept secret. The relationship between the key for decryption and the key for encryption in public key cryptography may be expressed as Kd!=Ke.
Public key cryptography uses both the secret key and the public key. The secret key is held privately but the public key is made public. The public key becomes problematic especially when the public key is copied or compromised by a third party. In this situation, the third party may intercept and obtain a sensitive document while the sender and/or the recipient is not aware of the attack of the third party.
To ensure that the public key is not copied or compromised, that is, to ensure the key integrity, public key infrastructure (PKI) has been developed. According to PKI, the public key and a certificate of the public key holder are made publicly available. As the certificate is a document signed by a trusted authority, others cannot modify the contents of the document. Thus, even if the document is compromised, falsification of the certificate can be detected using the signature.
Public key cryptography provides for simple key management as compared to the symmetric key system. However, complexity of the encryption and decryption algorithm is increased in PKI, thereby resulting in decreased processing speed. Thus, the load may greatly increase when the size of the message increases. RSA, developed by Rivest, Shamir, and Adleman, is a public key system that has been prevalently used.
Data communications between devices or between a server and devices also need to ensure and validate that the recipient receives the correct message from the sender and that the sender is an authenticated user. Furthermore, communications between the server and the devices require registration and authentication prior to commencing normal communication therebetween. In this regard, various authentication methods are under consideration to provide for mutual communication.
FIG. 1 depicts a conventional home network system. In FIG. 1, the home network system 100 includes a home server 110 and more than one device 120a through 120d. The devices 120a through 120d may be home appliances such as refrigerators, air conditioners, televisions, audio systems, and the like. The home server 110 can be connected to the devices 120a through 120d over a wireless or wired communication connection. The devices 120a through 120d are controlled through communications between the server 110 and the devices 120a through 120d. 
The home server 110 can be connected to the devices 120a through 120d using a cable. Recently, consideration is given to communication methods using a wireless connection. Examples of a wireless communication connection are wireless local area network (WLAN), Bluetooth, and infrared communication (IrDA) connections.
As aforementioned, to control the devices 120a through 120d by the home server 110, the devices 120a through 120d should be registered to the home server 110 when the devices 120a through 120d are initially installed. If the home server 110 wirelessly communicates with the devices 120a through 120d, security of the communicated data and authentication of the devices 120a through 120d are required. In a wireless environment, device authentication is the crucial requirement to provide for secure communication. Authentication verifies whether the devices 120a through 120d allowed access to the home server 110.
In the related art, the device configuration adopts the authentication system using a password (e.g., a secret key), which requires a complicated setup procedure to input and verify password information to the server to register each the devices 120a through 120d by the user.
Alternatively, methods using certificates (e.g., public keys) of a universal plug and play (UPnP) security model are under consideration. These methods require that the user verify information related to the public key of the device. However, the verification requires the password of the device to be input, which makes configuration complex.
Thus, conventional device authentication is vulnerable in view of the security employed. Specifically, in password authentication, the password information may be exposed or lost when the user inputs the password information. In addition, the certificate authentication using dynamic host configuration protocol (DHCP)/auto IP is vulnerable to denial of service (DoS) attacks.